mercedes-benz 7-g scn coding and programmingeskiturkoto.com/scnkoding.pdf · 7-g scn coding and...

Mercedes-Benz7-G SCN coding and

programming

Screen by screen

process

7-G SCN coding and programming


Before starting the SCN coding it is worth remembering a few points.

1/ When fitting a new valve body to a 7g transmission care must be taken to remember

to remove the oil feed pipe from the old valve body and swap it over with the new valve

body, as failure to do this will result in loss of drive.Oil feed pipe location

Oil filler pipe needs swapping over when fitting new valve body.


722.9 transmissions continued:

When replacing the valve body on the 722.9 gearbox remember to remove the oil feed pipe from the shown location ,and fit as next page suggests.


Make sure the oil feed hose is correctly and firmly installedFrom old valve body assembly

It is simpler to install the pipe Into the gearbox (as shown here) and assemble the valve body on to it.


2/ When fitting a new 7g valve body it is important that the selector linkage is correctly located in the sliding gate, as it will be impossible to complete the start up procedure with autologic.

3/ When carrying out SCN coding and drive authorisation, it is essential that you have cleared all stored faults in all other control units, (especially engine ECU) and also have a good stable vehicle voltage : (battery charger correctly installed on the vehicle) . Also make sure the autologic is powered by its mains adapter.Failure to do this may result in SD flash programming failing and the control module may sustain permanent damage .


It is also worth remembering that if you are re-flashing the original 7-g transmission You will delete all previous saved gear change adaption data.And the smoothness of gear changing may indeed be worse than before .

note: problems such as harsh gear changing are hardly ever cured by re-flashing the 7-g valve body , however if a re-flash or control unit programming is carried out the learning process for range selector must also be carried out ,failure to do this will result in harsh gear engagement or a possible non start situation. Also a long road test to carry out gear shift adaptations will also be required.we have become aware that sometimes when fitting a 7-g transmission to a ML-164 or RCLASS -251 chassis range vehicle , If 7-g programming keeps failing it may be necessary to disconnect the ESP control unit electrically , and try again.The same applies to 211-219 chassis with SBC or ABR or xenon headlights, disconnect and try again. This can be due to can bus excess traffic .Re connect and clear codes when coding is complete .cautionWe would recommend that a short/quick test is carried out for all gearbox complaints and the Mercedes technical help desk is contacted before any 7-g transmission work is carried out . Note- an engine control unit update may also be required in some instances.Always ensure that there are no stored fault codes in engine control unit before carrying out SCN or control unit programming , as this could cause a programming failure.


Common code for Automatic transmission in limp-home mode,

fault codes P0717, P0718, P0722, P0723, P2767, P2768

Complaint: Automatic transmission 722.9 switches to limp-home while driving (gearshifts no longer possible) and/or one or more of the following fault codes are stored or current: 0717, 0718, 0722, 0723, 2767, 2768

Cause: Rpm sensor fault : Component Y3/8n2 (Internal speed sensor (VGS2)) is defective/not available /or open circuit . Or The signal from component Y3/8n3 (Output speed sensor (VGS)) defective/not available /or open circuit . ([VGS2).

NOTE : it is now possible to just replace the electric plate /control unit separately

on the 7-G 722.9 transmission , only on VGS-2 and VGS-3 boxes.

The transmission control unit, which is bolted onto the electro hydraulic controller unit (EHS), may only be replaced using the EHS repair kit (A000 270 17 00).

Parts Rep. kit A 000 270 17 00 contains, among other things, VGS3 electrical kit,

B3 oil guide pipe, oil filter, small parts, screws/bolts

NOTE: On vehicles with VGS-1 the whole 7-g valve body needs to be replaced as before.VGS 1 part numbers A 220 270 12 06 or A 220 270 14 06 or A220 270 10 06 or A220 270 11 06 ( any of these numbers are a VGS 1 EHS controller)


Important

There are two different repair options for the 7-g gearbox ,it is important you select the

correct repair procedure.

1/ only if the valve body has one or more of the following speed sensor fault codes stored or present,(0717,0718,2767,2768,0722,0723,) can you fit a sensor/control unit replacement part .

The part number of this kit it 000-270-17-00 (and is only valid on vgs-2 and vgs-3)

If other codes are present as well as speed sensor codes you CANNOT fit the repair kit.

2/ if you have any other codes as well as the speed sensor codes listed above the complete valve body must be replaced.

3/ if you cannot communicate with the old valve body you cannot fit the repair kit


7-g electric plate

EHS valve body


The following screen shots are typical of the on screen displays shown when coding a new 722.9 (7g) transmission valve body or a control unitInitial start up

Choose between installing a complete valve body or just the ECU and electrics plate.(please see previous warning pages for conditions of just ECU replacement)


Five steps will be displayed in initial start up, These must be performed in sequence.Step 1: checks the new ECU for initial flash programming update availability.

11

If replacing a complete valve body continue with the following screen shots .

If however you are only replacing the control unit/electric plate PLEASE JUMP TO THE LAST SECTION IN THIS WALKTHROUGH CALLED (CONTROL UNIT/ELECTRIC PLATE REPLACEMENT PROCEDURE.)

COMPLETE VALVE BODY REPLACEMENT


5

Begin procedure press start button.

Edit correct chassis number and confirm .

Step 1 SD flash programming


7

The next screen shows the two possible screens that may be displayed And the options are explained on the following page



Note at this point if the file is not found on autologic you may get the following message displayed.This means you will be required to visit the autologic web site to download file “7G-PRG” file , and then try SD flashing again.

Screen displayed if file is known on autologic



next

When the flash file is known to autologicthe sequence /screen shots are as follows.



When SD flash programming is completeMove to STEP 2 SCN CODING


Step 2: SCN automatic coding .Enter the chassis number and press startThis will generate a message saying

THE SCN DATA FOR THIS VEHICLE COULD NOT BE RETRIEVED.A LOG HAS BEEN GENERATED .PLEASE SEND THIS LOG TO AUTOLOGIC TO REQUEST THE SCN DATA .

Once the log has been received the SCN code will be generated by autologicsoftware department and you will be

contacted by telephone and asked to download the latest Mercedes update .once update has been downloaded ,try automatic SCN coding again and this time it will be successful. After the completion of SCN coding move on to step 3.

See following page :

STEP 3 Drive authorisationSTEP 3 DRIVE AUTHORISATION



Once ok has been pressed you will be asked to place selector lever in various positions starting with park –reverse-neutral- drive - and process complete message .

(Step 4) Selector sensor learning process



Selector sensor learning process Complete


Step 5 cycle ignition

Clear error codes in vehicle and carry out gear change adaptation road test. After smooth changes adapted, the process is complete.


END OF COMPLETE VALVE BODY

CODING INFORMATION

Please continue to next page for electric plate repair

7-G PROGRAMMING OF CONTROL UNIT /ELECTRIC PLATE ONLY WHEN REPLACING WITH PART NUMBER 000 270 17 00

THE FOLLOWING PAGES ONLY ARE ONLY IF YOU ARE REPLACING THE CONTROL UNIT /ELECTRIC PLATE

WITH PART NUMBER 000 270 17 00

OLD UNIT MUST STILL BE FITTED TO VEHICLE


THE FOLLOWING PAGES ONLY ARE ONLY IF YOU ARE REPLACING THE CONTROL UNIT

/ELECTRIC PLATE WITH PART NUMBER 000 270 17 00

OLD UNIT MUST STILL BE FITTED TO VEHICLE

Step 1 read old ECU data


6

After pressing ok the autologic will close and the valve body must be removed and the control unit /electric plate must be replaced and re-installed in the vehicle and the autologic reconnected.

Connect autologic and Then follow the initial start up menu as before.



Step 2 write EHS number


8

Step 2 write EHS number


5

Begin procedure press start button.

Edit correct chassis number and confirm .

Step 3SD flash programming


7

The next screen shows the two possible screens that may be displayed And the options are explained on the following page



Note at this point if the file is not found on autologic you may get the following message displayed.This means you will be required to visit the autologic web site to download file “7G-PRG” file , and then try SD flashing again.

Screen displayed if file is known on autologic



next

When the flash file is known to autologicthe sequence /screen shots are as follows.



When SD flash programming is complete

Move to STEP 4 AUTOMATIC SCN CODING

Step 3


Step 4 SCN automatic coding .Enter the chassis number and press startThis will generate a message saying

THE SCN DATA FOR THIS VEHICLE COULD NOT BE RETRIEVED.A LOG HAS BEEN GENERATED .PLEASE SEND THIS LOG TO AUTOLOGIC TO REQUEST THE SCN DATA .

Once the log has been received the SCN code will be generated by autologicsoftware department and you will be

contacted by telephone and asked to download the latest Mercedes update .once update has been downloaded ,try automatic SCN coding again and this time it will be successful. After the completion of SCN coding move on to next step .

Note: if the SCN coding cannot be obtained it is possible that the software engineer may ask you to download and complete the 8 step start up procedure, And then ask you to take another download and carry out the all start up steps again from step 2 onwards to enable the 7-g transmission to be coded correctly.


Step 5 This writes the data from the old control unit stored in step 1 into the new control unit

Values consist of ( the working and resistance values of the solenoid valves).


Step 5 This writes the data stored in step 1 into the new control unit(working and resistance values of the solenoid valves).


STEP 3 Drive authorisationDRIVE AUTHORISATION step 6


Once ok has been pressed you will be asked to place selector lever in various positions starting with park –reverse-neutral- drive - and process complete message .

Selector sensor learning processStep 7


Selector sensor learning process Complete



cycle ignition step 8

Clear error codes in vehicle and carry out gear change adaptation road test. After smooth changes adapted, the process is complete.


END OF ELECTRIC PLATE /CONTROL UNIT

CODING INFORMATION

Possible problems when coding

When trying to fit a new electric plate to an old valve body this is only possible if the old EHS is not a VGS 1 valve body. VGS 1 part numbers A 220 270 12 06 or A 220 270 14 06or A220 270 10 06 or A220 270 11 06 ( any of these numbers are a VGS 1 EHS controller)The autologic will automatically check this (at step 1 ) when you select ECU and electric plate repair at step 1 it will automatically check and if it is found to be VGS 1 then the following messages will occur , and the programming will be terminated.

VGS 1 termination of programming

1 2


VGS 1 termination of programmingcontinued

3

4

This means the only option you have is to fit a new complete valve body


7-g information

1/ To qualify for an electric plate only repair the vehicle must only have a speed sensor code of one or more of the following codes 0717-0718-0722-0723-2767-2768any other code in combination with these codes make the electric plate repair non applicable.

2/ If you cannot communicate with the old ECU you need to fit a complete valve body.

3/ The EHS numbers 220 270 12 06 and 220 270 14 06 or A220 270 10 06 or A220 270 11 06 are all VGS 1 boxes and therefore do not come under the electrics plate repair as VGS 1 boxes are not compatible with the new plateso if you had a VGS 2 or a VGS 3 box > 2005 onwards then all should be ok( seen on page 2 of control unit version page with autologic)

4/ make sure a stable voltage is present throughout the coding procedure (a battery charger is recommended).


5/ The brand new complete EHS control unit looks like it comes blank and just needs flashing and SCN coding and then all is ok. this is not the case , in fact it does have some values in from factory: IE :the resistance and working values from the solenoid valves ,and as this is done at factory it is already pre set on the new (seemingly) blank EHS(complete valve body)

if you purchase a new electric plate (000 270 17 00 ) this obviously cannot be pre coded at factory as the working values of the solenoid valves for your vehicle are not known , so the old ECU still needs to be fitted to the vehicle, then with autologic on vehicle establish communication with transmission/initial start up / and select ECU and electrics plate repair.

In step 1/ (read data) with autologic the old working values of the solenoid values are read and stored in autologic then remove valve body and fit the new electrics plate and re write the EHS number to latest number available and then carry out rest of process on autologic.

it seems the values that are retrieved from the old ECU are live data, and that is why the old valve body still has to be fitted to the vehicle for the values to be transferred correctly, if you just hang old unit on vehicle(with no solenoid valves fitted) this will transfer corrupt data and the gear change will be very harsh and unacceptable when programming is complete.


note: If you ever have a problem after flashing the EHS(valve body) or a electrics plate repair and you are not sure if the process has completed correctly ?(even if it seems to have completed the process via autologic) ) a good way to check is have a look in actual values for gearbox and look at the transmission oil temperature, if the temp displayed is (minus 50 degrees ) then something is wrong with the coding or it has not completed correctly.

(note : this is only possible to check when all the 5 steps have been completed).

It is also worth remembering that the control unit/ electric plate is coded to the vehicle and cannot be transferred to other vehicles once assigned to a vehicle .

-50pp

New 7-g transmission

From June 2010 a modified 7-g transmission came into production.

This modified transmission requires a new transmission oil part number 001 989 78 03

This oil is a different colour from the older 7-g transmission

New oil = A 001 989 78 03 this new oil is blue in colour

Old oil = A001 989 68 03 old oil is red in colour

Note: the oils are not interchangeable

The two transmission types can be visually identified by the following :

1/ The New 7-g has 4x large moulded indent marks in underside of sump pan ,

In comparison the old type has 4 x smaller indents.

Old type 7-g

New type 7-g


2/ the front section of the new 7-g sump pan has two raised sections for cable brackets

(as photo)which also makes it easier to identify.

3/ the new transmission also has a different internal filler pipe

new type which is green in colour The old type was white in colour


Note: the oil temperature for checking level is at least 45 degrees


End of information

mercedes-benz 7-g scn coding and programmingeskiturkoto.com/scnkoding.pdf · 7-g scn coding and...

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